3IEJ

Pyrazole-based Cathepsin S Inhibitors with Arylalkynes as P1 Binding Elements

• PDB DOI: https://doi.org/10.2210/pdb3IEJ/pdb

• Classification: HYDROLASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2009-07-22 Released: 2009-10-06 
• Deposition Author(s): Bembenek, S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.18 Å
• R-Value Free: 0.263 
• R-Value Work: 0.187 
• R-Value Observed: 0.191 

Literature

Pyrazole-based cathepsin S inhibitors with arylalkynes as P1 binding elements.

Ameriks, M.K., Axe, F.U., Bembenek, S.D., Edwards, J.P., Gu, Y., Karlsson, L., Randal, M., Sun, S., Thurmond, R.L., Zhu, J.

(2009) Bioorg Med Chem Lett 19: 6131-6134

• PubMed: 19773165 
• DOI: https://doi.org/10.1016/j.bmcl.2009.09.014
• Primary Citation of Related Structures:  
  3IEJ


• PubMed Abstract: 
  

  A crystal structure of 1 bound to a Cys25Ser mutant of cathepsin S helped to elucidate the binding mode of a previously disclosed series of pyrazole-based CatS inhibitors and facilitated the design of a new class of arylalkyne analogs. Optimization of the alkyne and tetrahydropyridine portions of the pharmacophore provided potent CatS inhibitors (IC50=40-300 nM), and an X-ray structure of 32 revealed that the arylalkyne moiety binds in the S1 pocket of the enzyme.

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Organizational Affiliation: 

Johnson & Johnson Pharmaceutical Research & Development, L.L.C., 3210 Merryfield Row, San Diego, CA 92121, USA. [e-mail]

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 49.97 kDa 
• Atom Count: 3,688 
• Modelled Residue Count: 442 
• Deposited Residue Count: 444 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Cathepsin S	A, B	222	Homo sapiens	Mutation(s): 1  Gene Names: CTSS EC: 3.4.22.27
UniProt & NIH Common Fund Data Resources
Find proteins for P25774 (Homo sapiens) Explore P25774  Go to UniProtKB:  P25774
PHAROS:  P25774 GTEx:  ENSG00000163131

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
599	C [auth A], D [auth B]	2-[3-{4-chloro-3-[(4-chlorophenyl)ethynyl]phenyl}-1-(3-morpholin-4-ylpropyl)-1,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridin-5-yl]-2-oxoethanol C29 H30 Cl2 N4 O3 IWTCFPKHJADUJG-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
599	BindingDB:  3IEJ	IC50: 220 (nM) from 1 assay(s)
	PDBBind:  3IEJ	IC50: 220 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.18 Å
• R-Value Free: 0.263 
• R-Value Work: 0.187 
• R-Value Observed: 0.191 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 113.264	α = 90
b = 37.192	β = 108.59
c = 105.863	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2009-10-06 
Deposition Author(s): Bembenek, S.

Revision History  

• Version 1.0: 2009-10-06
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2021-10-13
  Changes: Database references, Derived calculations
• Version 1.3: 2024-11-27
  Changes: Data collection, Refinement description, Structure summary